The present study aims at enhancing our understanding of the influence of the mouthpiece configuration on the amplitude of oral pressures generated during a maximum expiratory pressure maneuver and on the neuromuscular recruitment of expiratory muscles (more specifically of the internal oblique and the transverse abdominal muscles).

Enhancing our understanding of the influence of the mouthpiece configuration on oral pressures and on the neuromuscular recruitment of the internal oblique and the transverse abdominal muscles during a maximum expiratory pressure (MEP) maneuver is the primary goal of this study

Maximal Respiratory Mouth Pressures (MIP and MEP):

Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) are commonly used indices to assess respiratory muscle strength at the mouth.

MIP measures the strength of inspiratory muscles, while MEP assesses expiratory muscle strength.

These measurements are simple, convenient, and noninvasive. However, clear standards for these measurements are not well-established.

Choice of Mouthpiece:

We propose exploring different mouthpiece designs to know their impact on pressure measurements.

Influence of Mouthpiece Design:

The type of mouthpiece used can affect pressure measurements. Some investigators recommend including a small leak in the measuring circuit to dissipate pressure generated in the mouth and minimize measurement errors.

However, specific studies focusing on the influence of mouthpiece design on MEP and neuromuscular recruitment of expiratory muscles (such as the internal oblique and transverse muscles) during MEP maneuvers would be valuable.

Additional Considerations:

Factors like body position (sitting vs. half-lying) may also impact pressure measurements, although no significant differences were found in one study.

Among the objectives of our study, we aim at exploring ways to improve the accuracy and reliability of respiratory pressure measurements.

In summary, understanding the impact of mouthpiece design on oral pressures during MEP maneuvers is essential for accurate assessment of respiratory muscle function. Further research in this area could provide valuable insights for clinical practice and pulmonary function laboratories.

Inclusion Criteria:

• Age over 18

Exclusion Criteria:

• Any neuromuscular disease or condition susceptible to interfere with the results
• Pregnant women
• Any contraindications to the realization of maximal expiratory maneuvers, as defined in the ATS Pulmonary Function Laboratory Management And Procedure Manual (3rd Edition)
• Excessive abdominal gird, compromising ultrasonographic positioning of electrodes or altering signal quality